U.S. patent application number 11/434057 was filed with the patent office on 2006-12-07 for drive track for snowmobile or tracked vehicle.
Invention is credited to Denis Courtemanche, Jules Dandurand.
Application Number | 20060273660 11/434057 |
Document ID | / |
Family ID | 37480365 |
Filed Date | 2006-12-07 |
United States Patent
Application |
20060273660 |
Kind Code |
A1 |
Dandurand; Jules ; et
al. |
December 7, 2006 |
Drive track for snowmobile or tracked vehicle
Abstract
A track formed of a molded rubber base sandwiching a cord layer,
followed by a cross bar and a single layer of ply fabric extending
longitudinally of the track.
Inventors: |
Dandurand; Jules;
(Sherbrooke, CA) ; Courtemanche; Denis; (Richmond,
CA) |
Correspondence
Address: |
MANELLI DENISON & SELTER
2000 M STREET NW SUITE 700
WASHINGTON
DC
20036-3307
US
|
Family ID: |
37480365 |
Appl. No.: |
11/434057 |
Filed: |
May 16, 2006 |
Current U.S.
Class: |
305/166 |
Current CPC
Class: |
B62D 55/06 20130101;
B62D 55/244 20130101; B62D 55/24 20130101; B62M 27/02 20130101;
B62D 55/26 20130101; B62M 2027/027 20130101 |
Class at
Publication: |
305/166 |
International
Class: |
B62D 55/24 20060101
B62D055/24 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 2, 2005 |
CA |
2,509,059 |
Claims
1. A track for a tracked vehicule, comprising a molded rubber base
sandwiching a cord layer, followed by a cross bar and a single
layer of ply fabric extending longitudinally of the track.
2. The track of claim 1, wherein said cross bar is of a rod.
3. The track of claim 2, wherein said rod is made of composite
material.
4. The track of claim 1, wherein said cross bar is located at
spaced intervals along a longitudinal direction of the track
beneath profiles projecting from a ground engaging side of the
track.
5. The track of claim 1, wherein said cord layer comprises a dense
strand arrangement formed of a twist arrangement of strands.
6. The track of claim 5, wherein said dense strand arrangement
comprises at least 18 strands per inch for a cord of 1.25 mm.
7. The track of claim 5, wherein said dense strand arrangement
comprises high strength, light weight materials.
8. The track of claim 5, wherein said materials are selected in the
group consisting of Kevlar.TM., nylon, and polyester.
9. The track of claim 1, wherein said cord layer extends on the
rubber base and passes beneath the cross bar.
10. The track of claim 1, wherein said cord layer 32 is
discontinued at locations of the track where idler wheels of the
vehicule pass.
11. The track of claim 1, wherein said ply of fabric includes woven
man-made fibers.
12. The track of claim 11, wherein said man-made fibers comprise
nylon.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority on Canadian application no.
2,509,059, filed on Jun. 2, 2005. All documents above are herein
incorporated by reference.
FIELD OF THE INVENTION
[0002] The present invention pertains to a drive track and, more
particularly, to a track for snowmobiles or other tracked vehicles,
having an improved construction to decrease horse power, increase
top speed and improve durability of the track when the latter is
driven at high rotational speeds.
BACKGROUND OF THE INVENTION
[0003] Endless drive tracks for propelling, for example, a
snowmobile over snow, ice or other similar ground structure, are
known in the art. The mounting of this track to a snowmobile and
the mounting of such track on an all-terrain vehicle are well
known. The track has a ground engaging outer side and an inner side
that receives and supports, on the lower run thereof, a suspension
which may consist of a wheel assembly or a slide rail assembly,
both of which are also well known in the art.
[0004] Conventionally, the track rotates by means of a motor driven
sprocket unit at the forward end of the vehicle and idle drive
wheels are mounted at the aft end of the vehicle to support the
rear end of the track. Sprockets engage a series of lugs integrally
formed with the inner surface of the track.
[0005] With reference to FIG. 1, the endless body is generally
formed of a molded rubber base having, embedded therein, a first
layer of reinforcing fabric 38 extending longitudinally of the
track, a series of laterally spaced cord strands 40 which extend
between the first layer of fabric and beneath a rod 32, and a
second ply 36 fabric disposed above the rod 32. Such arrangement
has been shown to allow good track performance and longevity. It is
generally believed that an increased amount of fabric contributes
these performances. In areas of the track where there is no rod 32,
it is about at mid-thickness of the track where the fiber of the
rubber is the strongest, this line of zero stress in cross section
of the track separating the region of compressive stress from that
of tensile stress being known as the neutral fiber.
[0006] In spite of efforts in this field, there is still a need for
a lighter, cost effective track.
SUMMARY OF THE INVENTION
[0007] More specifically, there is provided a track for a tracked
vehicle, comprising a molded rubber base sandwiching a cord layer,
followed by a cross bar and a single layer of ply fabric extending
longitudinally of the track.
[0008] Other objects, advantages and features of the present
invention will become more apparent upon reading of the following
non-restrictive description of embodiments thereof, given by way of
example only with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] In the appended drawings:
[0010] FIG. 1 is a cross section of a track as known in the
art;
[0011] FIG. 2 is a perspective view of a portion of a track
according to an embodiment of the present invention;
[0012] FIG. 3 is a cross-sectional view of the of FIG. 2;
[0013] FIG. 4 is a graph of power as a function of speed, used by a
track according to the present invention, in a test without
traction; and
[0014] FIG. 5 is a graph of power as a function of speed, used by a
track according to the present invention, in a test including
traction.
DESCRIPTION OF EMBODIMENTS OF THE INVENTION
[0015] As shown in FIG. 2, a track 10 according to an embodiment of
the present invention comprises a ground engaging outer side 12 and
an inner side (not seen in FIG. 2).
[0016] As seen in the cross-section of FIG. 3, the track 10 is
formed of a molded rubber base 30 sandwiching a cord layer 32,
followed by a cross bar 34 and a single layer of ply fabric 36
extending longitudinally of the track.
[0017] The cross bar 34 may consists of a rod as known in the art,
made of composite material for example. It is located at spaced
intervals along the longitudinal direction of the track beneath the
profiles 14 projecting from the outer side 12 of the track.
[0018] The cord layer 32 comprises a dense strand arrangement
formed of a twist arrangement of strands, comprising for example at
least 18 strands per inch for a cord of 1.25 mm. The strands
include high strength, light weight materials such as man made
fibers, such as Kevlar.TM., nylon, and polyester fabric for
example
[0019] The cord layer 32 extends on the rubber base 30 and passes
beneath the rod 34.
[0020] The cord layer 32 may be discontinued at locations of the
track where the idler wheels pass.
[0021] The ply of fabric 36 includes woven man-made fibers such as
nylon for example.
[0022] As shown in FIGS. 4 and 5, the present track is found to
necessitate equal or less power, which goes against the current
belief in the industry that the greater the amount of fabric in the
track composition, the better the performances.
[0023] People in the art will appreciate that the present invention
provides, in contrast to a track standardly made in the art and
including an arrangement of rubber, a first ply fabric, cord, rod,
second ply fabric and rubber, a track comprising a single layer of
ply fabric, yielding a track of reduced thickness, weight and cost,
while maintaining target performances thereof in terms of power and
longevity. In particular, the present composition is shown to
decrease horse power, increase top speed and improve durability of
the track when the latter is driven at high rotational speeds. It
has also been found to optimize the so-called neutral fiber
bringing it closer to the outer side of the track.
[0024] The present track may be used for a range of tracked
vehicles.
[0025] Although the present invention has been described
hereinabove by way of embodiments thereof, it may be modified,
without departing from the nature and teachings of the subject
invention as defined in the appended claims.
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